With a new book just out, Britain’s highest profile Alzheimer’s sufferer and
right-to-die campaigner, Sir Terry Pratchett, tells Elizabeth Grice how
his diagnosis has given him a new lease of life.

So persistent and alarming have been the advance warnings of Sir Terry Pratchett’s impending mental decline that the oddest thing about meeting him is his apparent normality. It is five years since the comic fantasy fiction author announced his “embuggeration” , a very Pratchetty way of describing a diagnosis of Alzheimer’s disease. By now, you fear, he will be slowing up, imagination fogged, creative powers shrivelled as a walnut.

Instead of that, the little man in black is a delightful affront to medical science, looking wizardly well in his black fedora with a jaunty feather in the trim. His handshake is firm, his eyes piercingly bright. He talks for 90 minutes with great fluency – although it does occur to me after a while that his habit of answering questions with an anecdote, or another question, may be a way of playing for time.

A new book is out, one of three he is working on this year. Since the diagnosis, he has made two television documentaries, continued his international book promotion tours and become an industrious ambassador for assisted dying. Is this one miraculous burst of defiance before the dying of the light, or did they somehow get it wrong?

“I have to tell you that I thought I’d be a lot worse than this by now,” he says. “And so did my specialist. At the moment, it’s the fact that I’m well into my sixties [he is 64] that’s the problem. All the minor things that flesh is heir to. This knee is giving me a bit of gyp. That sort of thing. And I’m well into the time of life when a man knows he has a prostate. By the time you’ve reached your sixties you do know that one day you will die and knowing that is at least the beginning of wisdom.”

Pratchett has posterior cortical atrophy (PCA), a rare form of early Alzheimer’s, which affects the back part of the brain responsible for recognising visual symbols. Sometimes he cannot see the cup that is in front of him. Clumsiness is another of the symptoms. When he tremblingly puts his glass of juice down on a glass-topped table in his hotel suite, it makes a crash, as if he misjudged the distance, but then glass-topped tables are tricky. I might easily have done the same. You don’t know with Pratchett, and often nor does he, how much to attribute to his disease and how much is natural ageing. So far, the cognitive parts of his mind seem untouched.

“One of the first things to go was the touch-typing. Kind of a bugger , I thought. Fortunately, technology has come to my aid.” He now speaks his books to a computer through a voice-recognition programme, or dictates them to his assistant, Rob Wilkins, who reads back the words at the end of the day. The new novel, Dodger, a virtuoso tale that shuttles between the sewers and grand houses of Dickensian London, was “written” in nine months.

Is putting a book together more difficult now?

“Better! Easier!” he yelps. “If it all came back, I would probably stick with talking. Because we’re monkeys. We chatter. It’s easy to do. It’s mutable.”

And the imaginative side? Pratchett’s teeming brain has spewed forth 50 books, 39 of them set in the alternative realm of Discworld. He has sold 80 million and been translated into 38 languages. The fact that he was Britain’s bestselling living author of fiction before JK Rowling came along perversely adds to his achivement rather than diminishes it. Interwoven with historical figures such as Charles Dickens, Robert Peel and Disraeli, Dodger is convincing proof of his still galloping imagination. “Sometimes I wish I could do something to slow it down. My wife says she can hear me plotting in my sleep.

“I do not know if it’s all suddenly going to go blong. In terms of fit-for-purpose, my life is OK. By the time I’ve unlocked the chapel – the shed where I work – the computer is on and away I go. I probably know what the first word will be. The pattern goes like this: tappity, tap, tap tap. Do your work. Then go and feed the chickens. Then go and shoo the sheep out of the garden. It’s good to get out into the sunshine, do a few other things, then back to work and away you go.”

Pratchett and his wife, Lyn , who have been married for 44 years, live in what he calls “a Domesday manorette” south-west of Salisbury. I would dearly like to have seen his allegedly mouse-infested office with its six computer screens, gothic lectern, dusty books and assortment of skulls, but for some reason he is going to meet me “half way”. When I turn up at the Hilton Metropole hotel in Birmingham, a disappointingly un-Pratchett- like conference centre near the airport, there is something odd going on. A character in a long black cloak and cavalier’s hat with ostrich feather is hobnobbing with a group of over-made-up women. Another face-painted woman, wearing a wisp of green gauze and not much else, drifts by, causing no eyebrow to be raised. There is a peculiar hum about the place, as though a pantomime is about to start.

And in a way it is. “Didn’t they tell you?” exclaims Pratchett’s assistant Rob. Tell me what? That this is the opening day of the eighth Discworld Convention, a celebration – with seminars, merchandise, games, dancing and role-play – of the fantasy universe according to Pratchett, the pre-eminent imaginer of dragons, creator of Rincewind the magician, of Nanny Ogg and Granny Weatherwax, of the repulsive conman Moist von Lipwig. The fans’ weekend takeover is total. Areas of the usually staid hotel have been renamed and mapped – Sator Square, Krull, Wyrmberg, Unseen University and The Odium. It is a complicated place, requiring a Lonely Dysc guide and a spotters’ crib-sheet to help Discworld novices identify guests by their mannerisms and garb. It is completely, wondrously bonkers.

Serene in the middle of it all, with a plastic name-tag dangling around his neck, is Sir Terry, worshipped for his stories and now especially for his ability to keep them coming.

He sometimes sounds annoyed that his campaign to increase funding for dementia research and for the right to die with dignity has diverted interest away from his prodigious writing career. Does he ever regret making his predicament public? “Never for one single iota of a moment. Saving your presence, I do get annoyed when interviews are all about that, although I know it’s my own fault. But it gave me almost a new lease of life.”

Since he “stepped out”, as he puts it, people have started coming up to him in the street, in theatres, in cafés, to thank him. They tell him about their terminally ill mother, husband, grandmother who suffered needless protracted agonies and indignities. “They say, 'I’m not going to go the way my mother went.’ ” In 2009, his two-hour BBC documentary Living with Alzheimer’s won two Baftas and made him the public face of the disease. The following year, he gave the Richard Dimbleby Lecture, Shaking Hands with Death, arguing that a person in extremis should be able to make a decision to die when the balance of their mind is “level, realistic, stoic, pragmatic and sharp”.

He is dismayed that Tony Nicklinson, the severely disabled man who fought and last month lost an impassioned campaign to end his life, effectively had to starve himself to death. “I put his picture on the little lectern by my desk because I don’t want this guy forgotten. He was very clear about what he wanted and you cannot tell me that two doctors helping him to go to sleep [as in a Dignitas clinic in Switzerland], would constitute murder. It cannot be murder. The law says it’s murder so the law is most definitely wrong and needs to be changed. This poor guy was a prisoner of technology.”

Ideally, Pratchett wants to live his own life to the full and then, before the disease mounts its final attack and before words fail him in the most literal sense, to die in a chair on his lawn with Thomas Tallis on his iPod, a brandy in his hand and whatever modern version of the ''Brompton cocktail’’ a helpful medic can supply.

He has called the desperate little stream of travellers to Dignitas “the shame of Britain” and harks back to the days when doctors were unafraid to “help people over the step, and were expected to, without any words ever being said by the family”. It has never seemed likely that Pratchett himself would elect to die in a foreign country, but he is not inclined to share his shifting thoughts on the subject. “I have no road map,” he says, perhaps more to protect his wife than himself.

Will she support him in whatever he decides? “I believe this is going to be the case,” he says opaquely. “But we discuss it in oblique terms. We share the same temperament. She doesn’t like bullies – and in the opposition to assisted dying there is a certain amount of bullying: 'Because I believe in this God whom you do not, I insist that you are not allowed to die.’ ”

Does he have any sympathy with those whose religious beliefs set them against assisted suicide? Pratchett veers off, as is his way. “Would it surprise you if I say that often when I’m gardening I’m singing hymns?” And he launches into a Sunday school favourite that must have been excised from Hymns Ancient & Modern long ago:

“Over the world there are small brown babies/ Fathers and mothers and babies dear/ They do not know the love of Jesus/ No one to tell them that he is near…”

He has a certain affection for the Church of England, because it “understands the English”, and he recently gave a lot of money to a small church near his home “because I don’t think we should let good churches go.” But does he believe in God?

“Do you?” he parries. “If Jesus suddenly walked in I would like to have a really good conversation with him but I’m not going to take anyone’s word for it beyond that. I don’t believe in the war god of the Israelites. He’s a bogeyman. Jesus preached the golden rule, by and large.”

He recalls a strange moment in the second euthanasia documentary he made, Terry Pratchett: Choosing to Die, about three men with degenerative illnesses. One was Peter Smedley, who had motor neurone disease, filmed in his dying moments at Dignitas. “When it was over, Erica, our statuesque nurse, opened the window and said, 'I have no religion but I believe the soul leaves the body within 36 hours of death.’ I was freaked out anyway and I freaked out even further. I think that kind of ambiguity is being human.”

There is a sharp drollness about Pratchett, son of a motor mechanic, that gives his books their edge and will spice the autobiography he is writing. He has just finished the chapter On Being Rich. “There is a soak-the-rich attitude in the air, a feeling that if you have a lot of money you must have got it by some ghastly means. I can quite happily say there was never any family money. All the money we got was mine, just from writing books.”

His pride is not misplaced. The Pratchetts were a happy but thrifty family whose idea of a holiday was a week in Lyme Regis with friends. Terry was a forensic sort of boy, fond of expeditioning and experiments. “My father encouraged me to do all the Just William things. He was never so pleased as when I electrocuted him by setting up a little device in his shed to give him a shock when he opened the door.” Crystal sets, astronomy, science… if the boy had a legitimate passion, his parents encouraged it.

He came to reading late, through a chance encounter with The Wind in the Willows. It detonated a love of books “similar to Hiroshima” and his real education began thereafter at the Beaconsfield public library, where he “read like a mowing machine”.

He was a journalist in his native Buckinghamshire and then a press officer for the Central Electricity Generating Board, writing science-fiction novels in the evenings, before deciding to write full-time. For security, his mother hoped he would get a proper job in an office again. Only when he bought his parents a new house was she reassured that he must be doing all right.

I make a foolish comment to the effect that he is a very lucky man. In the circumstances, he could have issued a devastating put-down but just gives one of his glittering stares. “Yes,” he says. “And the harder I work, the luckier I become.”

Money means that he will not have to worry about his wife after he is gone. It means he can afford the Alzheimer’s drug Aricept, which he is too young to receive free under the NHS. He has donated £500,000 to Alzheimer’s research. He can experiment with strange treatments, such as the flashing helmet with light rays that may rejuvenate his brain cells. And he hopes that when the time comes he will be able to buy the right kind of care to die well.

“The word 'care’ has come to have the same aura to it as the term 'workhouse’,” he says. “Like most people, I would rather die at home. I’m certainly going to be buried

at home. I have enough ground. And the nice thing is that it would be sacred ground at last.”